This type of situation depends on the terms and conditions of your tenancy, you can either serve a notice or find someone who can replace you and continue the remaining timeframe of your tenancy.
Make sure to review the agreement of your tenancy and look for a break clause, if there is a break clause from your contract this can let you serve a notice to your landlord advising for an early termination to the contract that was before made, make sure the notice is served within the terms of the break clause from the contract.
On the other hand, if within your contract is a tenancy agreement that allows replacement tenancy clause which enables a replacement of one tenant from another one, then you can switch your tenancy to others. By doing this make sure to inform your property manager about the matter as soon as possible. To increase the possibilities of finding a new tenant try consulting from craigslist, social media, references from family and friends and gumtree.
The Marble Property Group can help you carry out all other necessary administrations provided you have found someone to replace you. A basic fee will be charged for the replacement, this fee is basically for Referencing the whole party which includes the guarantors, taking out details from current and past employers, financial credit checks, and arranging the agreement for the new tenant.
If the process of replacement is still ongoing, you the current tenant will still be held reliable for the rent and other responsibilities a tenant is obliged to do, and this will stop until the new tenant or replace tenant will pass the referencing and have signed the agreement. In an event that the new tenant failed the referencing then you need to provide a new tenant that may replace you from the property soon.